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The following list summarizes the physical characteristics of DeviceNet.

•

Trunkline-dropline cabling—main trunk cable with a drop cable for 
each device

•

Selectable baud rates of 125 K, 250 K, and 500 K

•

Support for up to 64 devices—each device identifies itself using a 
MAC ID (Media Access Control Identifier) from 0–63

•

Device removal/insertion without severing the network

•

Simultaneous support for both network-powered and self-powered 
devices

•

Various connector styles

For complete information on how to connect your National Instruments 
hardware onto the DeviceNet network, refer to your getting started manual.

The DeviceNet Specification uses object-oriented modeling to describe the 
behavior of different components in a device, how those components relate 
to one another, and how network communication takes place. The 
following paragraphs briefly describe object-oriented modeling and how 
these concepts are used within the DeviceNet Specification.

In object-oriented terminology, a classification of components with similar 
qualities is called a 

. For example, different classes of geometric 

shapes could include squares, circles, and triangles. Figure A-1 shows 
various classes and instances of geometric shapes.

Table A-1.  DeviceNet Baud Rates and Wiring Lengths

125 Kb/s

500 m (1640 ft)

6 m (20 ft)

156 m (512 ft)

250 Kb/s

250 m (820 ft)

6 m (20 ft)

78 m (256 ft)

500 Kb/s

100 m (328 ft)

6 m (20 ft)

39 m (128 ft)